Study on Fatigue Damage Accumulation and Fatigue Life of Asphalt Binder Under Different Load Levels and Temperatures

Asphalt binder is a critical component of asphalt pavement, and fatigue damage is a primary failure mode. Characterizing its fatigue performance is important for evaluating asphalt pavement performance and design. This study investigates fatigue damage accumulation of 70# asphalt binder under different strain levels and temperatures using time sweep tests. At 20 °C, increasing strain from 1.5% to 3.5% reduces fatigue life from 17,380 to 2020 cycles, an 88.4% reduction. Asphalt undergoes a hardening stage under the action of LVE load. When asphalt is subjected to NLVE fatigue load, plastic flow changes its viscoelastic properties without a hardening stage. Fatigue damage accelerates, and fatigue life decreases with increasing load level and decreasing temperature. A damage accumulation model considering dissipated energy history and a temperature‐dependent fatigue life prediction model () are established based on fatigue test data. Among them, c increasing from 3.72 × 10 11 at 10 °C to 2.67 × 10 12 at 20 °C.